docs: def count(self, eventRegistry):
          """
          return the number of articles that match the criteria
          @param eventRegistry: instance of EventRegistry class. used to obtain the necessary data
          """
          self.setRequestedResult(RequestEventArticles(**self.queryParams))
          res = eventRegistry.execQuery(self)
          if "error" in res:
              print(res["error"])
          count = res.get(self.queryParams["eventUri"], {}).get("articles", {}).get("totalResults", 0)
          return count